The present invention relates to a vehicle wiper device. More specifically, the vehicle wiper device wipes the surface of a rear door glass which is a hatch glass.
In recent years, station wagons and hatchbacks provided with a rear door glass which is a hatch glass have been in use. The rear door glass is provided on a rear door that selectively opens and closes a luggage compartment. The rear door glass is rotatably opened and closed independently of the opening and closing of the rear door. The entire vehicle wiper device that wipes the surface of the rear door glass is sometimes directly mounted on the rear door glass.
However, an actuator of the vehicle wiper device is large and heavy among components of the vehicle wiper device. Therefore, if the actuator is mounted on the rear door glass, more operating force will be necessary to open the rear door glass. Furthermore, when closing the rear door glass, an impact caused when the rear door glass collides with the rear door is increased. As a result, a large load is applied to part of the rear door glass where the actuator is fixed, and the rear door glass might get broken. Furthermore, since a motor for driving the actuator is also mounted on the rear door glass, a structure for supplying power to the motor becomes complicated.
Therefore, Japanese Laid-Open Patent Publication No. 2000-233722 discloses a vehicle wiper device in which an actuator is fixed on a rear door, and a pivot shaft is rotatably supported on a rear door glass. The pivot shaft supports a wiper arm to rotate integrally with the pivot shaft.
The actuator rotates an oscillating disk having a coupling bore at a predetermined angle. The pivot shaft includes a lever having a coupling pin. When the rear door glass is closed, the coupling pin is inserted in the coupling bore, so that the actuator is drivingly coupled to the pivot shaft. When the oscillating disk is rotated, the lever is rotated within a rotation angle range, and as a result, the wiper arm is rotated in a reciprocating manner. When the rear door glass is open, the coupling pin is disengaged from the coupling bore. Thus, the rear door glass is easily opened and closed without hindrance.
A pivot holder supporting the pivot shaft has restrictors, which restrict the rotation of the lever beyond the rotation angle range. The restrictors prevent the wiper arm from hanging down in such a manner that the wiper blade interferes with the rear door. However, an allowance, which is created between the rotation angle range and the restrictors, accommodate component size variations and assembly variations. The allowance prevents the lever from colliding with the restrictors every time the wiper operates. Therefore, the lever might slightly deviate from the rotation angle range. In this case, the appearance of the vehicle might be spoiled.